I've built a zvh turbo and when fitting the turbo and manifold back to the engine the manifold was sitting on the block, so i got the grinder out and knotched a small amount of metal out of the way (as much as possible, on the blocked off oil return lump bit of the block) yet i think i'm still gona have to use 2 exhaust gaskets to give me a couple of mm clearance. Is there any way round this?